Method of perforating the necks of aerosol containers

ABSTRACT

This disclosure relates to a novel method of and apparatus for perforating the necks of aerosol containers including means for or the steps of providing an aerosol end for two or three piece containers having an annular shoulder joined by a radius to a cylindrical neck closed by an end wall, positioning the neck in exterior telescopic relationship to a punch having a circumferential axially terminal cutting edge, supporting the aerosol end in its telescoped position by seating of the end wall upon an end face of the punch, providing an annular guide ring with an internal diameter corresponding generally to the outer diameter of the neck, disposing axis of the punch and guide ring in coincidence with each other, and in parting relative telescopic movement between the punch and guide ring to sever by a ripping action under tension the end wall from the cylindrical neck while at the same time sandwiching the latter between the inner and outer diameters of the ring guide and punch, respectively.

Hoenig et al.

[ Oct. 7, 1975 METHOD OF PERFORATING THE NECKS OF AEROSOL CONTAINERS[75] Inventors: James Robert Hoenig, Tinley Park;

Salvador Cariasa Mallorca, Chicago, both of I11.

[73] Assignee: Continental Can Company, Inc.,

New York, N.Y.

[22] Filed: Nov. 15, 1974 [21] Appl. No.: 524,146

[52] US. Cl. 113/120 AA; 83/685; 225/93;

225/103 [51] Int. Cl. B21D 51/40 [58] Field of Search 83/684, 685, 686,687,

83/688, 689, 690, 691, 565, 566, 567, 568, 569,570; 113/1 G,7 A, 12011,120 Z, 120 AA; 225/93, 103, 104

[56] References Cited UNITED STATES PATENTS 120,162 10/1871 Mullen83/688 237,439 2/1881 Jenkins 83/688 2,337,182 12/1943 Calleson et al.113/120 H 3,706,292 12/1972 Saunders 113/120 H X 3,724,305 4/1973 Kondo83/688 X 3,726,244 4/1973 Arangelovich 113/120 AA X FOREIGN PATENTS ORAPPLICATIONS 19,994 2/1895 United Kingdom 83/688 1,063,625 8/1959Germany 83/690 Primary Examiner-J. M. Meister Assistant ExaminerFred A.Silverberg Attorney, Agent, or FirmDiller, Brown, Ramik & Wight [57]ABSTRACT This disclosure relates to a novel method of and apparatus forperforating the necks of aerosol containers including means for or thesteps of providing an aerosol end for two or three piece containershaving an annular shoulder joined by a radius to a cylindrical neckclosed by an end wall, positioning the neck in exterior telescopicrelationship to a punch having a circumferential axially terminalcutting edge, supporting the aerosol end in its telescopedposition byseating of the end wall upon an end face of the punch, providing anannular guide ring with an internal diameter corresponding generally tothe outer diameter of the neck, disposing axis of the punch and guidering in coincidence with each other, and in parting relative telescopicmovement between the punch and guide ring to sever by a ripping actionunder tension the end wall from the cylindrical neck while at the sametime sandwiching the latter between the inner and outer diameters of thering guide and punch, respectively.

4 Claims, 3 Drawing Figures US. Patant 00. 7,1975 3 919. 2 3

PRIDR ART METHOD OF PERFORATING THE NECKS OF AEROSOL CONTAINERS Aerosolcontainers are normally constructed from two or three pieces dependingupon whether the container body is open ended and has double seamthereto a bottom end or whether the container body is drawn as aone-piece unit composed of an integral body wall and bottom end. In eachcase, however, a separate top end unit, generally a domed configuration,is double seamed to the remaining open end of the container body and inaerosol containers this end is generally domed and has a cylindricalneck which is subsequently curled for the application thereto of aconventional dispensing valve. Typical of such aerosol containers may befound in commonly assigned patents to Elmer J. Boik, U.S. Pat. No.3,549,058, issued Dec. 22, 1970 entitled END UNIT AND LINER FOR AEROSOLCON- TAINERS; Herbert S. Ruekberg, U.S. Pat. No. 3,700,136, issued Oct.24, 1962, entitled END UNIT AND LINER FOR AEROSOL CONTAINERS; and JamesW. Kinnavy, U.S Pat. No. 3,519,171, issued July 7, 1970 and entitled:DISPENSING CONTAINER WITH METERING AND DELAYED VALVE MECH- ANISM.

End units or closures of conventional aerosol containers are formed byblanking or stamping process and in conjunction with the usual domed endpanel, initially include an upper annular shoulder joined at a junctureto a cylindrical wall of a neck which in turn is enclosed by an endwall. It is the end wall which must be perforated or removed to permitfurther fabrication of the neck, such as the curling thereof heretoforenoted, prior to the application of a value thereto. In the past, theremoval of the end wall was through the use of an aligned perforatingpunch and guide ring having a cut edge with the latter elements formingconventional portions of conventional slide dies. The cut edge of theguide ring and the exterior surface of the perforating punch generallyhad a clearance therebetween of approximately 0.005 inch, however, dueto the fact that conventional slide dies do not contain leader pins itis extremely difficult to obtain desired alignment of the punch to theguide ring cut edge. Basically one must rely for such alignment on theexperience of a press operator or maintainer.

Alignment gauges are known for the purpose of avoiding the latterproblem of misalignment at perforating stations for aerosol containersin slide dies. Though such gauges are reliable, their use is very timeconsuming because the punch assembly must be removed from the press, thegauge inserted, and the die pulled manually through the press by hand toassure alignment and permit adjustment which cannot, of course, beperformed if the press were under power. After alignment, the gauge isremoved, the punch assembly is again installed, and the press may berun. Needless to say down time due to such alignment is a very costlyitem when considering the tens of billions of aerosol end units whichare manufactured in this fashion.

In keeping with the present invention, the cut edge of the guide ring istotallyavoide d and the system is selfaligning thereby resulting in lesspress down time between changes of guide rings and/or punches.

From an apparatus standpoint, there is provided a punch having agenerally cylindrical exterior surface and a terminal end face uponwhich rests the end wall of an aerosol end unit, a juncture between theexterior end face and the terminal end of the punch defines an axiallyterminal circumferential cutting edge, and an annular guide ring devoidof a cut edge is moved relative to the punch such that upon relativetelescopic movement between the punch and guide ring:

a. The aerosol neck is initially sandwiched between the inner and outerdiameters of the guide ring and punch, respectively,

b. An axial force is applied against the annular shoulder of the aerosolend unit whereby the neck unit is placed under tension, and

c. Ripping of the end wall at its juncture with the neck occurs underthe influence of tension forces at the cutting edge of the punch wherebyat the completion of the telescopic movement the end is ripped from theneck and the latter is completely sandwiched between the guide ring andpunch.

In further keeping with this invention the punch is preferably a tubularelement and has associated therewith a knock out rod or pin which movesaxially relative to a bore of the tubular punch to drive the ripped endwall of the aerosol end unit through the bore for the purpose ofdischarging the same.

IN THE DRAWING FIG. 1 is an exploded fragmentary sectional view of aconventional punch and die assembly for perforating aerosol end units,and illustrates a clearance between a cut edge of a guide ring and apunch (FIG. 1a) in the manner in which the cut edge cooperates with thepunch to sever the end wall from the aerosol end unit neck.

FIG. 2 is a fragmentary sectional view of an apparatus constructed inaccordance with this invention, and illustrates a guide ring absent theconventional cut edge and the manner in which the neck of a container isinitially sandwiched between an interior surface of the guide ring andan exterior surface of the punch.

FIG. 3 is a view identical to FIG. 2, but illustrates the completion ofthe severing operation at which the neck of the end unit is sandwichedbetween the punch and guide ring while the ripped end wall thereof isdischarged by a knock out pin.

For the purpose of better understanding the present invention referenceis first made to FIG. 1 of the drawing which exemplifies typical punchand die assemblies for perforating or cutting the end walls from aerosolend units, the end unit illustrated being generally referred to by thereference 10 and having a dome 11, an annular shoulder 12, a neck 13, aradius 14, and a cylindrical end wall 15. The end unit 10 is positionedatop a punch 16 with the end wall 15 resting upon an upper terminal face17 of the punch 16. The punch 16 is generally of a tubular configurationhaving an outer cylindrical surface 18 and an inner stepped surface 19.The punch 16 is, of course, assembled to a conventional press in a knownmanner.

A generally annular guide ring 22 is also conventionally mounted in thepress in generally axial alignment with the punch 16. The conventionalguide ring 22 has a step lower shoulder (unnumbered) defining aconventional cut edge 23 which has a clearance C of approximately 0.005inch relative to the surface 18 of the punch 16. Thus, upon relativemovement between the punch 16 and the guide ring 22, the cut edge 23contacts the end unit generally in the vicinity of the radius 14 and incooperation with the outer surface 18 of the punch 16 continuing actionresults in the severance of the end wall (FIG. lb) and a downwarddescent of the end unit 10 relative to the upper face 17 of the punch16, as is most apparent in FIG. 1b. A typical knock out rod or knock outpin 24 descends vertically during the operation of the press to drivethe severed end wall 15 through the bore 19 of the punch 16 forsubsequent discharge.

Upon the opposite motion of the knock out pin 14 and opposite relativetelescopic motion of the punch 16 and the guide ring 22 suitable ejectormeans are pro vided for stripping the now perforated or opened neck endunit 10 from the punch 16.

As was mentioned earlier conventional slide dies do not include leaderpins and this makes the alignment of the punch 16, particularly thesurface 18 thereof, to the cut edge 23 of the guide ring 22 extremelydifiicult, again reliance being placed upon that of an experienced pressmaintainer. Through experience or through the use of an alignment gaugethe prior art system as exemplified in FIG. 1 is operative but the downtime due to alignment results in such cut edge and perforating punchcombinations to become very costly from a production standpoint,particularly in view of the high quantity production carried on in theaerosol industry.

In keeping with the foregoing, the present invention (FIGS. 2 and 3) isutilized to likewise perforate or open the end wall 15 of a conventionalaerosol end unit adapted for being double seamed in a conventionalmanner to a one-piece or two-piece can. Since the end unit of FIGSJ2 and3 is identical to that of FIG. 1 added prime reference numerals havebeen applied thereto. However, in the case of the present invention agenerally annular guide ring includes an outer cylindrical surface 31, alower annular terminal surface 32 and an inner cylindrical surface 33devoid of the conventional cut edge 23 of conventional guide rings 22(FIG. 1).

A punch 35 of the invention includes an outer cylindrical surface 36with an upper end portion of the punch 35 being stepped to define acylindrical upper surface 37 of a diameter less than that of thediameter of the surface 36. The surface 37 of the punch 35 merges withan annular end face 38 of the punch and at a juncture between thesurfaces 37, 38 is an annular cutting edge 39 of the punch 35. A typicalknock out pin 40 is utilized for removing the end wall 15' after thesame has been ripped from the neck 13' at generally the juncture 14', aswill be described immediately hereinafter.

Assuming that the punch 35 and guide ring 30 are separated, an aerosolend unit 10' is positioned upon the punch as shown in FIG. 2 with theclearance between the surfaces 36, 33 being such as to accommodate thethickness of the neck wall 13'. Upon relative telescopic motion betweenthe punch 35 and the guide ring 30 by the conventional press heretoforementioned, the annular end face 32 of the guide ring 30 is brought tobear against the annular shoulder 12' of the aerosol end unit 10'. Atthis point no severing action has taken place (FIG. 2). Upon continuedrelative telescopic motion between the guide ring 30 and the punch 37the material of the neck 13 is placed under tension as the guide ring 30applies downward forces against the annular shoulder 12' while the punch36 applies upw wardly directed forces against the end wall 15 Whenplaced under sufficient force the material at generally the juncture 14'fails under tension thus ripping the end wall 15 from the neck 13'generally along the radius 14' as the latter is in contact withrelatively sharp edge 39 of the punch 35. The stepped surface 37 of thepunch 35 facilitates the ripping operation due to the fact that thesharp cutting edge 39 is not positioned exactly at the apex of thejuncture l4 and therefore a gradual bending of the radius 14' occursprior to its failure under tension.

At the conclusion of the perforating operation the neck 13 is sandwichedtotally between the surfaces 33, 36 of the guide ring 30 and the punch35, in the manner best shown in FIG. 3. Due to this sandwiched conditionany irregularities in the ripped edge 41 can be at least moderatelysmoothed or ironed out. The knock out pin 40, of course, operates in themanners heretofore described relative to the knock out pin 24 to removethe now severed end wall 15' from the assembly through the bore(unnumbered) of the punch 35.

Upon reverse relative reciprocation of the guide ring 30 and the punch35 the now perforated aerosol end unit 10 may be removed for subsequentprocessing, such as the curling of the neck 13' and the subsequentapplication thereto of a dispensing valve.

Due to the construction of the apparatus of FIGS. 2 and 3 the heretoforementioned down time necessary for aligning conventional guide ring cutedge and punch is totally eliminated and, more important or just asimportant is the fact that the assembly is self-aligning particularlywhen used in presses having slide dies devoid of leader pins.

While preferred forms and arrangements of parts have been shown inillustrating the invention, it is to be clearly understood that variouschanges in detail and arrangement of parts may be made without departingfrom the spirit and scope of this disclosure.

I claim:

1. A method of perforating the necks of aerosol containers comprisingthe steps of providing an aerosol end for two or three piece containershaving an annular shoulder joined by a radius to a cylindrical neckclosed by an end wall, positioning the neck in exterior telescopicrelationship to a punch having a circumferential axially terminalcutting edge, supporting the aerosol end in its telescoped position bythe seating of the end wall upon an end face of the punch, providing anannular guide ring with an internal diameter corresponding generally tothe outer diameter of the neck, disposing axes of the punch and guidering in coincidence with each other, and imparting relative telescopicmovement between the punch and guide ring to a. initially sandwich theaerosol neck between the inner and outer diameter of the guide ring andpunch, respectively,

b. apply an axial force against the aerosol annular shoulder whereby theneck is placed under tension, and

c. ripping the end wall under the influence of the tension forces at thecutting edge whereby at the completion of the telescopic movement theend is ripped from the neck and the latter is completely sandwichedbetween the guide ring and punch.

2. The method as defined in claim 1 wherein the punch is tubular andthere is provided the additional step of moving a knock out pin in axialalignment with the punch and guide ring.

4. The method as defined in claim 2 wherein the step of moving the knockout pin takes place after the end wall has been ripped from the neck.

1. A method of perforating the necks of aerosol containers comprisingthe steps of providing an aerosol end for two or three piece containershaving an annular shoulder joined by a radius to a cylindrical neckclosed by an end wall, positioning the neck in exterior telescopicrelationship to a punch having a circumferential axially terminalcutting edge, supporting the aerosol end in its telescoped position bythe seating of the end wall upon an end face of the punch, providing anannular guide ring with an internal diameter corresponding generally tothe outer diameter of the neck, disposing axes of the punch and guidering in coincidence with each other, and imparting relative telescopicmovement between the punch and guide ring to a. initially sandwich theaerosol neck between the inner and outer diameter of the guide ring andpunch, respectively, b. apply an axial force against the aerosol annularshoulder whereby the neck is placed under tension, and c. ripping theend wall under the influence of the tension forces at the cutting edgewhereby at the completion of the telescopic movement the end is rippedfrom the neck and the latter is completely sandwiched between the guidering and punch.
 2. The method as defined in claim 1 wherein the punch istubular and there is provided the additional step of moving a knock outpin in axial alignment with a bore of the tubular punch to drive theripped end wall through the bore for the purpose of discharging thesame.
 3. The method as defined in claim 2 wherein the step of moving theknock out pin takes place in conjunction with the step of impartingrelative movement between the punch and guide ring.
 4. The method asdefined in claim 2 wherein the step of moving the knock out pin takesplace after the end wall has been ripped from the neck.